Standard: GB /T 13829.1
Available sizes: 1.5 to 6 (7 sizes)
| Standard Body | Standard Number |
|---|---|
| EN | EN 28740 |
| GB | GB /T 13829.2 |
| DIN | DIN EN ISO 8740 |
| ISO | ISO 8740 |
| Size | P | k_max | k_min | s_max | s_min | k_nominal | ds_nominal |
|---|---|---|---|---|---|---|---|
| 1.5 | 2 | 0.25 | 2.84 | 1.975 | 0.18 | 0.8 |
| +0.05，0 |
| 2 | 3 | 0.4 | 6.4 | 2.975 | 0.3 | 1.2 | ±0.05 |
| 2.5 | 5 | 0.63 | 17.6 | 4.97 | 0.5 | 1.7 | ±0.05 |
| 3 | 8 | 1 | 45.2 | 7.964 | 0.8 | 2.6 | ±0.05 |
| 4 | 12 | 1.6 | 101.8 | 11.957 | 1.2 | 3.8 | ±0.1 |
| 5 | 20 | 2.5 | 283 | 19.948 | 2 | 6 | ±0.1 |
| 6 | 25 | 3 | 444 | 24.948 | 2.5 | 7.5 | ±0.1 |
Standard corrosion protection for indoor and mild outdoor environments.
Salt spray: 96–200 hours | RoHS compliant (trivalent chromium)
High-performance coating for automotive, marine, and harsh environments.
Salt spray: 720–1500 hours | Recommended for grade 8.8+
Heavy-duty protection for structural and outdoor applications.
Salt spray: 500–1000 hours | Thread tolerance adjustment required
Note for high-strength fasteners (Grade 10.9, 12.9): Electroplating processes require hydrogen embrittlement relief baking (minimum 4 hours at 200°C within 4 hours of plating). Contact our engineering team for grade-specific plating recommendations.
Request detailed technical specifications, material certifications, and availability information for your application requirements. Our engineering team can provide product recommendations, custom specifications, and technical documentation.
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